Gmat Prep2?/ (Different Integers)

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Gmat Prep2?/ (Different Integers)

by dferm » Thu May 15, 2008 6:51 pm
Please help..

Thanks...
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by sandeep_chhabra » Thu May 15, 2008 10:12 pm
For the median of different five numbers to be 70:

a,b,70,c,d

as we know that median is the number in between the largest and the smallest number, when numbers are arranged in either ascending order.

its obvious that:
a<b<70<c<d

therefore c and d are the largest numbers and also greater than 70. hence 1) is sufficient.

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should the answer not be A

by prabhu3645 » Fri May 16, 2008 7:56 am
Option 2, what if all the numbers are 70 in the set. The average is 70 but none of the numbers is greater than 70.
pls explain if 70 is considered greater than 70.

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Re: should the answer not be A

by sandeep_chhabra » Fri May 16, 2008 8:40 am
prabhu3645 wrote:Option 2, what if all the numbers are 70 in the set. The average is 70 but none of the numbers is greater than 70.
pls explain if 70 is considered greater than 70.
prabhu3645 If we read the question carefully it says : Five DIFFERENT numbers. So all the five numbers cannot be 70.

:)

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by dferm » Fri May 16, 2008 10:16 am
THE ANSWER TO THIS QUESTION IS D...

BUT DON"T SEE HOW...

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by sandeep_chhabra » Fri May 16, 2008 10:26 am
dferm wrote:THE ANSWER TO THIS QUESTION IS D...

BUT DON"T SEE HOW...
dferm, its true that the answer is D each statement is sufficient.

since you had chosen 2) i guessed that you know why 2nd is sufficient andso i explained why 1) is sufficient.


1) is sufficient: let the 5 no. be:
1,2,3,4,340
so the sum of these 5 no. is 350 and avg is 70
now if u take the avg of the greatest 2 no. i.e. 4 and 340 it is equal to 172 which is greater than 70.

so 1 and 2 each statement is sufficient

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by dferm » Fri May 16, 2008 10:28 am
I actually guessed on this one...

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by sandeep_chhabra » Fri May 16, 2008 10:31 am
i hope i was able to help you. :)

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by dferm » Fri May 16, 2008 10:35 am
Can you explain a little how B could be the answer as well...

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by sandeep_chhabra » Fri May 16, 2008 10:48 am
I guess by B you mean the statement 2.


lets take some numbers whose average is 70 as mentioned in statement 2

10,20,30,40 ,250
sum=350, avg=70
questions says is the average of the 2 greatest integers in the list greater than 70
if you take the avg of greatest 2 numbers ie. 40 & 250 then it is 145 which is greater than 70

take another set of numbers,
60,65,70,75,80
avg is 70 and sum of greatest 2 no. ie. 75 and 80 is greater than 70


this shows that if the average of 5 no. is 70 then then avg of GREATEST 2 no. would be GREATER THAN 70.

you can try this with a few set of numbers.

let me know if any doubt.

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by dferm » Fri May 16, 2008 11:00 am
Thanks ur the best...